Sample Iptables configurations A sample iptables output that I am using on an OpenVPN server to allow Internet traffic to be passed through it. ubuntu ~ $ sudo iptables-save # Generated by iptables-save v1.4.21 on Wed Aug 2 22:19:48 2017 *filter :INPUT ACCEPT [2654934:1228315333] :FORWARD ACCEPT [31023:17433690] :OUTPUT ACCEPT [2475842:555885003] COMMIT # Completed on Wed …

How to define a string and print it out with the printf() function. #include <stdio.h>   /* Defining a global string. */   #define hi "Hello Sire."   int main(void) { /* Printing out the string. */ printf("%s\n", hi);   return 0; }#include <stdio.h> /* Defining a global string. */ #define hi "Hello Sire." int …

This function will allow your computer to speak. function shellspeak() { mplayer “http://translate.google.com/translate_tts?tl=en&q=$(echo $@ | sed ‘s/\s/+/’)” > /dev/null 2>&1; } A script that will change all files in a directory to lowercase filenames. function lowercase() # move filenames to lowercase. { for file ; do filename=${file##*/} case “$filename” in */*) dirname==${file%/*} ;; *) dirname=.;; …

This is a very simple Hello World program in C. int main() { write(1, "Hello World\n", 14); }int main() { write(1, "Hello World\n", 14); } Counting how long a text string is. #include <stdio.h> #include <string.h> #define MSG "Hello Doctor, let’s get back to the TARDIS!" int main() { int g; g = strlen(MSG); if …